Technical Field
The present invention relates generally to active cooling systems and more particularly to liquid heat exchanger systems for removing heat from electronic components and devices.
Background Art
Consumer electronic devices such as personal computers commonly utilize microprocessors and other circuit components that generate heat. Such circuit components can include for example central processing units, video graphics processing units, chip sets and memory modules. During use, heat generated within these circuit components must be removed to avoid both damage to the electronic device and reduction in device performance.
Conventional active cooling systems have been developed to extract heat from circuit components in electronic device applications such as personal computers. Such conventional active cooling systems can include the use of fans mounted on or near a circuit component to force air across the circuit component or across a heat exchanger mounted to the circuit component. Forced convection can transfer heat away from the circuit component in these conventional systems. Another conventional active cooling system includes the use of a closed-loop fluid circuit including a cooling fluid, a fluid reservoir, a pump, a heat exchanger or radiator and a contact block. The contact block generally includes the region where the cooling fluid engages in thermal contact with the heat generating circuit component, i.e. a central processing unit, microprocessor, graphics card, etc. Also, in such conventional systems, movement of the cooling fluid through the closed-loop system is provided by an external pump.
In many applications, the space surrounding the circuit component to be cooled inside the electronic device does not provide adequate room for a closed-loop active liquid cooling system. Thus, it may be necessary to position one or more cooling system components outside the electronic device housing where there is sufficient space. This type of system can be referred to as remote cooling.
One problem associated with conventional active remote cooling systems of this nature involves the use of numerous individual components. For example, some conventional systems include a pump coupled to a reservoir, a heat exchanger, and a contact block engaging the circuit feature to be cooled, wherein each system component is connected by one or more conduits or hoses. This type of system requires at least three connection hoses—an outlet hose extending from the heat exchanger to the pump, a delivery hose extending from the pump to the contact block, and an inlet hose extending from the contact block back to the heat exchanger. Each hose end must be securely connected to a system component, leading to at least six hose connection locations. Such conventional designs requiring three hoses and a standalone pump undesirably add complexity and potential leakage locations to the active cooling system.
Another problem associated with some conventional active liquid cooling systems for electronic devices includes the placement of the inlet and outlet orifices in the heat exchanger. For example, U.S. Pat. No. 6,234,240 to Cheon teaches a fanless cooling system for a computer having a reservoir with an inlet opening generally positioned at a higher elevation than the exit opening. By positioning an opening in the reservoir at a relatively high elevation on the electronic device, such conventional devices create an enhanced possibility of damage to circuit components if a leak should develop at the elevated opening position during use.
Another problem associated with conventional active liquid cooling systems for electronic devices is placement of all cooling system components inside the electronic device. Such internal system component placement can require disassembly of the electronic device if replacement, repair or alteration of any individual component is necessary. Disassembly of the electronic device in such instances can be time consuming and costly and can increase the likelihood of damage to other system components or the electronic device itself during disassembly.
What is needed then are additional improvements in the devices and associated methods of actively cooling circuit components in electronic devices using closed loop liquid circulation systems.